I'm not so sure what caused adult acne. I get it once in awhile, maybe because of hormonal imbalance when where getting old. I hate it when I get it cause it's disgusting and ugly, when I noticed that I'm getting breakouts I apply my anti acne cure right away. I always have in hand acne medication just in case I will get breakouts on the wrong day. I also recommend my medication to my friends because it works well on me.